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81.

Purpose

The aim of this study was to evaluate the efficacy of mesenchymal stem cells (MSCs) in a nitrofen-induced congenital diaphragmatic hernia (CDH) rat model.

Methods

Pregnant rats were exposed to nitrofen on embryonic day 9.5 (E9.5). MSCs were isolated from the enhanced green fluorescent protein (eGFP) transgenic rat lungs. The MSCs were transplanted into the nitrofen-induced E12.5 rats via the uterine vein, and the E21 lung explants were harvested. The study animals were divided into three: the control group, the nitrofen-induced left CDH (CDH group), and the MSC-treated nitrofen-induced left CDH (MSC-treated CDH group). The specimens were morphologically analyzed using HE and immunohistochemical staining with proliferating cell nuclear antigen (PCNA), surfactant protein-C (SP-C), and α-smooth muscle actin.

Results

The alveolar and medial walls of the pulmonary arteries were significantly thinner in the MSC-treated CDH group than in the CDH group. The alveolar air space areas were larger, while PCNA and the SP-C positive cells were significantly higher in the MSC-treated CDH group, than in the CDH group. MSC engraftment was identified on immunohistochemical staining of the GFP in the MSC-treated CDH group.

Conclusions

MSC transplantation potentially promotes alveolar and pulmonary artery development, thereby reducing the severity of pulmonary hypoplasia.  相似文献   
82.

Background/aim

Sodium is thought to be critical to growth. Infants who have an ileostomy may suffer from growth faltering, as sodium losses from stomas may be excessive. Urinary sodium measurements may indicate which patients could benefit from sodium supplementation; however, there is no consensus on what level of urinary sodium should be the cutoff for intervention. Our aim was to determine whether there is a relationship between urinary sodium and growth in infants undergoing ileostomy, colostomy and cystostomy.

Methods

Following audit approval, a retrospective observational study of patient notes and chemical pathology data was carried out. All infants <1 year of age that had an ileostomy, colostomy, or cystostomy procedure between February 1997 and January 2014 were included. Patients’ weights, urinary and serum sodium and potassium levels and clinical variables were recorded until discharge. Weights were converted to Z-scores for analysis.

Results

Forty patients were identified whose notes were available for review and who had at least three urinary sodium measurements. During their hospital stay, 11 (28 %) maintained weight within normal limits (Z-scores ?2 to +2, 15 (38 %) were moderately malnourished (?3 to ?2) and 14 (35 %) severely malnourished (30 mmol litre. Electrolyte data were not normally distributed so that correlations between electrolytes and growth were tested using the non-parametric Spearman rank correlation coefficient. Urinary sodium levels positively correlated with growth (r = 0.3071, p < 0.0001), as did serum sodium levels (r = 0.2620, p = 0.0059) whereas there was no relationship between urine or serum potassium and growth.

Conclusions

Poor growth is frequent in this group of patients and appears to be linked with sodium levels. Further work is necessary to draw up guidelines for appropriate sodium supplementation.  相似文献   
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Journal of NeuroVirology - The recent pandemic outbreak of coronavirus is pathogenic and a highly transmittable viral infection caused by Severe Acute Respiratory Syndrome Coronavirus 2...  相似文献   
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Multimodal imaging is a recent idea of combining two or more imaging methods synergistically to overcome the weakness of individual imaging modalities and utilizing complementary benefits. Ultrasound (US) and magnetic resonance imaging (MRI) are widely used imaging techniques in healthcare and to fully utilize the potential of fusion imaging, dual-modal contrast agents are necessary to improve disease diagnosis by enhancing contrast resolution and reducing health risks associated with the dual dosage of contrast agents. In this study, magnetic microbubbles were synthesized by incorporating oleic acid stabilized superparamagnetic iron oxide nanoparticles (OA-SPIONs) into lecithin microbubbles, encapsulating the perfluoropentane (PFP) core. The magnetic microbubbles were characterized by FTIR, SEM, MFM, zeta potential, in vitro MRI, and ultrasound. Upon in vitro MRI, magnetic microbubbles showed a negative contrast effect by producing darker T2 weighted images. Magnetic microbubbles showed concentration-dependent response with a decrease in signal intensity with an increase in the concentration of OA-IONP in microbubbles. However, a decrease in acoustic enhancement was also observed with an increase in OA-IONP concentration, therefore concentration was optimized to achieve the best effect on both modalities. The magnetic lecithin microbubble with 10 mg SPIONs provided the best contrast on both US and MR imaging. The hemocompatibility testing resulted in hemolysis less than 7% with plasma recalcification time and thrombin time of 240 s and 6 s corresponding to excellent hemocompatibility. Thus the magnetic microbubbles with a phase convertible PFP core encapsulated by a lecithin shell loaded with OA-SPIONs can serve as a potential bimodal contrast agent for both US and MRI imaging.

The magnetic microbubbles with phase convertible PFP core encapsulated by lecithin shell loaded with OA-SPIONs can serve as a potential bimodal contrast agent for both ultrasound (US) and magnetic resonance imaging (MRI).  相似文献   
90.
Hymen imperforation is uncommon. Symptoms include primary amenorrhea, cyclical lower abdominal pain, and rarely a pelvic mass syndrome. Delayed discovery may lead to endometriosis and infertility. Pelvic ultrasound and nuclear magnetic resonance detect associated genito‐urinary malformations. Hymenectomy is the standard surgical treatment.  相似文献   
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